Among the many trends in telecommunications, increasing Internet traffic is probably the most obvious. Behind this explosive growth are the millions of new users, richer content like multi-media, and the migration of corporate voice and data traffic onto the Internet. Today, escalating Internet traffic demands are pushing beyond the limits of today's switching architectures, forcing carriers to rethink their network strategies. An entirely new generation of highly scalable switching technology is necessary to meet the requirements of today's network users. In addition, digitized information can be combined not only with other voice conversations, but it can be then merged with other formats such as facsimile, video and Internet traffic. Convergence implies that the collective conglomeration of media formats and sources is more efficiently transported on a single network rather than individual special use networks. The physical work and right a way access rights required to lay fiber creates an economy of scale such that digging one trench is easier than several parallel trenches.
Telecommunication carrier owners are understandably reluctant to discard billions of dollars of legacy equipment yet realize that the Public System Telephone Network (PSTN) will need to evolve into something completely different to handle the demands of today's users. Because the volume of telecommunications traffic is predominantly data, it is no longer sensible to create and maintain two parallel networks, one for voice and a second one for data. Voice and data networks are converging. Most carriers agree that the equipment using either Asynchronous Transfer Mode (ATM) or Internet Protocol (IP) is much less costly and more efficient than circuit switching. Distributive software paired with a packet-based architecture can now achieve the same functionality as a Class 5 telecommunications switch. Industry players are realizing that the “Softswitch” is the answer to transforming PSTN networks into a more flexible, scalable solution that can accommodate the increasing data traffic and provide the carriers with the ability to generate revenue through value-added services. Consequently, Softswitch architectures are emerging as the next-generation solution to converged voice and data networks.
Softswitch is a concept of separating the network hardware from network software. In traditional circuit switched networks, hardware and software is not independent. Circuit switched networks rely on dedicated facilities for inter-connection and are designed primarily for voice communications. The more efficient packet based networks use the IP protocol to efficient route voice and data over diverse routers and shared facilities.
As a number of new services deployed every day, traditional switches reached a scalability limit, where service delivery time is far in excess of modern business requirements. The service execution environment scalability can be measured by the number of services, the number of application services, and the service delivery time. The reasons of the slow service delivery in the traditional switches may result from the complexity of integration and the complexity of integration of the new service with other existing services.
In addition, a next generation network is adding new complexities to the problems including an increase in the number of service execution environments (e.g., proxies, end user devices, application servers, media servers, etc.), a more diversity of service execution environment (e.g., SIP, Parlay, IN, etc.), and a need to integrate applications developed by several vendors, who are not necessarily following the same service implementation philosophy.